Problem while OS-Update

Hello,
upgrading my OS from RedHat 8.0 to FC2, postgresql was also
automatically updated from 7.2. to 7.4. Unfortunately, I did not
"dumpall"... How can I get my data??? I copied the data-folder to
another location and so got running the new postgresql-server. I tried
to install the old 7.2.4.tar.gz in a new folder, but it don't go further
than ./configure. gmake gives the following lines at the end: (second
time tiping gmake)

gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations
-Wl,-rpath,/usr/local/pgsql/lib -export-dynamic access/SUBSYS.o
bootstrap/SUBSYS.o catalog/SUBSYS.o parser/SUBSYS.o commands/SUBSYS.o
executor/SUBSYS.o lib/SUBSYS.o libpq/SUBSYS.o main/SUBSYS.o
nodes/SUBSYS.o optimizer/SUBSYS.o port/SUBSYS.o postmaster/SUBSYS.o
regex/SUBSYS.o rewrite/SUBSYS.o storage/SUBSYS.o tcop/SUBSYS.o
utils/SUBSYS.o -lz -lcrypt -lresolv -lnsl -ldl -lm -lbsd -lreadline
-ltermcap  -o postgres
commands/SUBSYS.o(.text+0x420a): In function `DoCopy':
: undefined reference to `errno'
commands/SUBSYS.o(.text+0x4210): In function `DoCopy':
: undefined reference to `errno'
commands/SUBSYS.o(.text+0x4317): In function `DoCopy':
: undefined reference to `errno'
commands/SUBSYS.o(.text+0x431d): In function `DoCopy':
: undefined reference to `errno'
collect2: ld returned 1 exit status
gmake[2]: *** [postgres] Fehler 1
gmake[2]: Leaving directory `/usr/local/pgsql/postgresql-7.2.4/src/backend'
gmake[1]: *** [all] Fehler 2
gmake[1]: Leaving directory `/usr/local/pgsql/postgresql-7.2.4/src'
gmake: *** [all] Fehler 2
[root@whisky postgresql-7.2.4]#

There were a lot of lines containing "...Wmissing..."

How can I proceed?

Thanks for help

Heiko